Paraseptal emphysema of the upper lobe of the left lung is usually not serious. Paraseptal emphysema of the upper lobe of the left lung is a restrictive form of emphysema and is a common type of emphysema. It affects predominantly young people, who usually have a history of smoking, occupational dust exposure, or recurrent respiratory infections. Most people develop paraseptal emphysema of the upper lobe of the left lung in association with chronic inflammatory conditions such as old tuberculosis and chronic obstructive pulmonary disease. Chronically infected lesions can pull on the surrounding alveoli during resorption, resulting in enhanced translucency, and restrictive emphysema will be detected on CT. Due to its anatomical location, restrictive emphysema has very little effect on the human body and hardly causes any symptoms, such as cough, sputum, fever, etc. In most cases, it is detected during physical examination, so there is no need for special treatment. However, patients should undergo regular chest CT examination to clarify whether the emphysema shows progressive changes.